One stands to the right of East Ender's impoverished plant (8)
I believe the answer is:
brassica
'plant' is the definition.
The answer is an example.
'one stands to the right of east ender's impoverished' is the wordplay.
'one' becomes 'a' (a thing is one thing).
'stands to the right of' is a charade indicator (letters next to each other) (some letters go to the right of others).
'east ender's impoverished' becomes 'brassic' ('brassic' is Cockney slang meaning poor).
'a' after 'brassic' is 'BRASSICA'.
(Other definitions for brassica that I've seen before include "Eg, cabbage, turnip, rape" , "Turnip and cabbage genus" , "Plant genus including many vegetables" , "Plants such as cabbage and brussels sprouts" , "Cabbages, broccoli etc." .)